Lubrication System Schematic
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| Illustration 1 | g01177316 |
Lubrication System Schematic | |
The metering devices are a progressive piston type metering device that is used to accurately distribute lubricant to the lubrication points. The metering devices differ in the number of outlets. However, the operation of the metering devices are identical.
After lubricant is discharged from pump (1), the lubricant enters main lubrication line (2). The lubricant then enters main metering device (3). The lubricant then goes to secondary metering devices (4), (5), and (6). Also, the lubricant may be routed directly to a lubrication point.
Inside the metering devices, internal pistons move in a given progressive sequence and in repeating cycles. Each piston must complete an entire movement before the next piston is able to move.
All of the pistons are independent. The pistons cannot be interchanged with another piston. If the piston is removed, the piston must be returned to the original cylinder.
Components
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| Illustration 2 | g01177319 |
The following components in the boom foot section are shown in Illustration 2:
- Main metering device (3)
- Secondary metering device (4)
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| Illustration 3 | g01177322 |
Secondary metering device (5) is located on the machine, as shown. See Illustration 3.
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| Illustration 4 | g01177323 |
Secondary metering device (6) is located on the machine, as shown. See Illustration 4.
Sequence of Operation
Phase 1
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| Illustration 5 | g01177325 |
(7) Inlet port (8) Piston (9) Passage (10) Passage (11) Passage (12) Outlet port (13) Passage | |
Pressurized lubricant that is sent by pump (1) enters the metering device at inlet port (7). The lubricant flows through passages (9) and (13) to the right side of piston (8). Lubricant shifts piston (8) to the left. Lubricant in the left side of piston (8) flows through passages (10) and (11). The lubricant then flows out of outlet port (12) .
Phase 2
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| Illustration 6 | g01177329 |
(8) Piston (14) Outlet port (15) Passage (16) Passage (17) Passage (18) Passage (19) Piston | |
When piston (8) is at the extreme left position, passage (17) opens. Lubricant flows through passages (17) and (18). This lubricant shifts piston (19) to the left. Lubricant in the left side of piston (19) flows through passages (15) and (16). The lubricant then goes out at outlet port (14) .
Phase 3
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| Illustration 7 | g01177337 |
(19) Piston (20) Passage (21) Outlet port (22) Passage (23) Passage (24) Passage (25) Piston | |
When piston (19) is at the extreme left position, passage (22) opens. Lubricant flows through passages (22) and (24). This lubricant shifts piston (25) to the left. The lubricant in the left side of piston (25) flows through passages (23) and (20). The lubricant then goes out at outlet port (21) .
Phase 4
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| Illustration 8 | g01177341 |
(25) Piston (26) Passage (27) Outlet port (28) Passage (29) Passage (30) Passage (31) Piston | |
When piston (25) is at the extreme left position, passage (28) opens. Lubricant flows through passages (28) and (30). This lubricant shifts piston (31) to the left. The lubricant in the left side of piston (31) flows through passages (29) and (26). The lubricant then goes out at outlet port (27) .
Phase 5
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| Illustration 9 | g01177344 |
(8) Piston (10) Passage (13) Passage (19) Piston (25) Piston (31) Piston (32) Passage (33) Passage | |
When piston (31) is at the extreme left position, passage (33) opens. Lubricant flows through passages (33) and (10) to the left side of piston (8). Lubricant shifts piston (8) to the right. The lubricant in the right side of piston (8) flows through passages (13) and (32). Lubricant then goes out at outlet port (34) .
As the sequence continues, pistons (19), (25), and (31) will shift in sequence from the left position to the right position. This completes one cycle.
Note: Once the supply of lubricant is interrupted, the pistons stop moving and no lubricant is distributed. When lubrication is started again, the cycle will continue from the last stopped piston.
Note: The entire system is monitored at the pressure relief valve of the pump. If lubricant goes out at this valve, this indicates a blockage in the system.